Ram initialization and small c.

Peter Stuge stuge-linuxbios at cdy.org
Wed Mar 5 21:24:01 CET 2003

On Tue, Mar 04, 2003 at 11:25:18AM -0500, Jeremy Jackson wrote:
> Another idea on the subject:
> On some chipsets, the entire range of supported processors have MMX and
> maybe SSE/SSE2.  MMX gives 8 extra 64 bit registers (nobody uses
> floating-point in LinuxBIOS, right?) that can be used as 32bit.  They
> can't be used as address/index/base, but only for data. See the MOVD
> instruction.

Likewise, st0..st7 in the FPU could be used as a stack-like 8x64bit data
storage, IIRC.  I seem to remember that Pentium MMX CPUs share st* space
with MMX registers however, so for those platforms one of them will have
to do.


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